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Reality check- hybrids, fuel efficiency

WE WASTE SO MUCH! I think an important point needs to be made here on driving habits. I can only speak about Americans because this is where I drive. Since I ordered my Escape Hybrid and started reading about them, I made a major change in my driving habits.

People own SUV's for different reasons just like people who own fast sports cars, Vans, trucks and small cars. Money, image, noise, repair, fuel, use and many other reasons are why they select a certain vehicle.

Look around, most Americans are living in the fast lane. If the stress or car accidents don't kill us, the pollution will.

"REALITY CHECK - HYBRIDS, FUEL EFFICIENCY" A good title. For me, I had a real reality check on why I was spending so much money on gas. It was my driving habits. I took off fast at lights and was fighting to stay in front of the slow pokes that would delay my time on the road. Time was my enemy on the road.

My Hybrid has changed my driving habits. Best therapy anyone could give someone with bad driving habits. When I drive now, I see the madness on the road. I was that madness and wasted gas and polluted to the hilt. No more, I now get better MPG than the EPA ratings.

Hybrids are addicting and good for everyone till something better comes along.

Reality check- hybrids, fuel efficiency

I like to see an energy balance break down before I drop my scepcism about hybrid cars. Despite several requests on bloggers' sites nobody ever provided me one.
Hybrid cars are in the end powered by their combustion engine and have to overcome the energy losses from their electric charge/store/discharge/propel driveline. (at best an efficiency ratio of 13%. So 85%plus of the energy generated by the combustion engine to enable the electric powerline IS WASTED !!!!!)
On top of that comes extra weight for the batteries.
All those losses have to be offset by 1) regeneration of brake energy and 2) more optimal running zone of the combustion engine.
Can't believe that it makes sense. Those good EPA numbers could have been derived by running a car with full batteries in the 20 (or so) minute cycle the test takes. At least they should test them with empty batteries too and average.
You can also make a traditional car more fuel saving by applying certain aspects of some hybrids. Like underpowered engines, high pressure tires, narrow treads, (gas-)engine turn-off at each stand-still. However, the discomforts accepted in hybrids are commercially viable in traditional cars. So in some way we're also comparing apples and oranges.
I therefore wouldn't be surprised if hybrid are just a passing fad. Just good marketing by the predominently Japanese manufacturers until somebody really exposes the weaknesses in the logic of the concept. Nobody has been able to find a perpetuum mobile as yet !!!!

Reality check- hybrids, fuel efficiency

I don't need an "energy breakdown" of any kind to see the benefits of owning a hybrid. Here's all the breakdown I need:

Petroleum-based fuel prices will probably never go down. Only up.

Hybrid cars get better fuel efficiency than a pure petrol-based car of the same body style.

That's it.

Sure, hybrids might be a passing fad, but at least its gonna help me where I need help most...the wallet. The emissions factor, the performance factor, the availability factor...none are as important as that almighty dollar that's gonna be left in my pocket 3 weeks after I fill-up when I still have over 1/4 of a tank left.

Naysayers laugh now, but when I pull up to the gas pump and think to myself, "damn, I haven't been here in a month;" that's when I'll be laughing.

Reality check- hybrids, fuel efficiency

"I like to see an energy balance break down before I drop my scepcism about hybrid cars. Despite several requests on bloggers' sites nobody ever provided me one."

Frank, I guess your skeptical about Hybrids as far as I can follow you here. I'm not sure a "bloggers' site" can answer your question, what ever that is. You make alot of assumption about Hybrids, the EPA, Marketing by the Japanese and logic of the concept of Hybrids.

Alot of people though the earth was flat at one time. Now, Tim just pointed out that better MPG is what he gets with his Hybrid in tring to answer your question.

You don't believe in Hybrids and you want answers, right! About your fully charged battery theory and the EPA. I can drive my Escape Hybrid with a fully charge battery at 30 MPH on elec. only for 1.6 miles before the engine starts and has to charge the battery. The engine charges the battery for about the same distance to have another fully charged battery. Say I got 30MPG with the engine pushing the car and charging the battery at the same time. That would mean I'm getting 60 MPG. Now the EPA sets city driving at 36 mpg. I can get 40mpg and the engine is not broke in yet.

Your high tire presure suggestion is good but what about safety and traction? Narrow treads? What about plaining in the rain. Marketing Japanese? Not much marketing, only waiting list from what I see. Logic? saving gas and the environment is a good logic I think.

Reality check- hybrids, fuel efficiency

Hey Galileo,
The earth is sure not flat. And narrow tires are in fact less prone to aqua planing. Yes ... you read it correctly. Narrow tires have a better downward pressure per sq inch and so press the water better away than those wide macho super slicks people love to have under their cars. The same is true for traction in snow. (If you would go water skiing what do you think would float you better over the water, a couple of thin rods or wide boards.)
Clearly wide tires have a lot working for them too. E.g. better dry footprint, better heat dissipation, less hysteresis to name a few. So when choosing a technical solution you go for wider tires (up to a certain extent).
As for narrow high pressure tires; if I not mistaken (but I sure could be in this) look under your Prius. Would that be the kind of tires you would go for under a regular car. Pretty skimpy, huh. And what is the prescribed pressure? The usual 30psi or a tad higher?
Just start to think. Where does the energy come from in a hybrid, ..... other than from that same old gas in the tank in the back.
So how can it be that a hybrid can be more efficient than the gasoline driveline by which it is ultimately powered? Or did we miss something and did somebody invent a perpetuum mobile and slip it in without anybody noticing?
Just ask yourself this question and I'm sure that you too will wonder about the energy balance of this miraculous concept.

Reality check- hybrids, fuel efficiency

Frank asks "how can a hybrid be more efficient than the driveline upon which it is based?"

Fair question. The answer is that ultimately it isn't, of course. However, the hybrid has a number of tricks up its sleeve that allow it to capture more of the energy than a conventional car with the same engine would. Regenerative braking is the most obvious example of this. However, Prius and its related designs can also capture additional power from the engine when it's being run at less than peak output by siphoning off that energy to the battery (or to the traction motor). Since gasoline engines are more efficient at or near their peak output than they are at lower outputs, this is more efficient than a conventional auto which would just run the engine at a less efficient RPM/load.

There's also the factor that a hybrid's gasoline engine is smaller than an otherwise identical conventional car's would be. Because the eletric motor can assist with peak power requirements, the engine can be sized closer to the average power requirements of the vehicle instead of the peak power requirement.

At a given vehicle size and performance level a well designed hybrid will therefore always be more efficient than an otherwise identical conventional car.

Reality check- hybrids, fuel efficiency

And don't forget that the engine isn't wasting gas idling at a stop/in traffic.

Also, with models that can run in electric mode (such as Prius, Escape, etc.), they're saving a lot of gas when starting from a dead stop, which burns a lot of fuel comparatively. Electric is a lot more efficient than ICE in this respect.

Efficiency is increased by the combination of two types of propulsion with different strengths. Each gets used where it is most efficient, as well as the electric being able to recover and re-use energy that is otherwise wasted.

Reality check- hybrids, fuel efficiency

Frank, I agree about the thin tire theory and I'm sure most here would agree. I took your original statement that you thought that having thinner groves (threads) in the tire would somehow improve mileage. Boy, you sure jumped hard on that issue and not any of the main issues discussed. Do you work for Dodge or GM?

Reality check- hybrids, fuel efficiency

Today our weather was fair and had warmed up to around 70 degreese.
Over the 46 miles I travel to work I did almost 66 MPG in my HCH today.
ALmost sixty six.
After driving over 640 miles it's almost time to fill my 11-12 gallons of gas again. Will likely calculate to around 59MPG again.

With gasoline over $2.10 per gallon this car is as efficient as I need.

That's my reality.

Frank, you mentioned the weight of the batteries. If you were referring to the heavy lead-acid batteries of the EV cars, we don't use those. We use a deep-cycle version of the Nimh batteries, similar to the one in your notebook computer. Only weighs a few pounds.